The manufacture of a number of articles requires the addition of lengths of cut material to a moving web of material. Often, the material to be added to the moving web is in the form of long strips of tape material, usually stored on a parent roll. The tape material is fed into the apparatus, wherein desired lengths of the tape material are transferred onto the moving web of material.
Methods of placing lengths of tape material fed as a continuous strip are well known in the art. WO 03/037769 A1 is to an apparatus in which lengths of tape material are cut from the long strip and are subsequently transferred by a rotating member such that they are placed onto the moving web of material in the same orientation as the direction of movement of the web. The leading edge of the length of tape material is contacted first with the moving web and then the remainder of the strip is laid or rolled onto the surface of the web with the trailing edge contacting last.
A more complex situation arises when the length of tape material is to be placed in a transverse orientation to that of the direction of movement of the web of material. If the type of apparatus described in WO 03/037769 A1 (above) is used, then there is a tendency that the strips will be misaligned when placed onto the web. This is because the tape material is fed in a direction perpendicular to that of the moving web. Therefore, after the leading edge of the strip has been contacted with the moving web, by the time the trailing edge is contacted, the leading edge has already moved a distance in the same direction as the moving web. This also has the unfortunate effect of causing pleats or folds to be created in the moving web due to the leading edge being in contact with the web, but the trailing edge still being in contact with the transfer element of the apparatus, the pleat being formed as the leading edge moves away from the apparatus in a perpendicular direction, yet the trailing edge does not as it is still in contact with the transfer element, thus pulling the web of material towards the transfer element.
There exist apparatuses that can manipulate both the speed and direction of a desired length of tape material. The first is that of Couillard et al, U.S. Pat. No. 6,227,541 B1, which utilizes a multiple conveyer assembly for rotating and placing a strip of material on a substrate. However, such an apparatus is large, cumbersome, and requires a high level of maintenance. This also suffers from the further disadvantage that the speed of product throughput is also reduced as the tape material cannot simply be contacted leading edge first followed by trailing edge to the web as in WO 03/037769 A1, rather it requires careful placement manipulated by a number of sequential steps.
A second way of changing the direction of the length of tape material is achieved by Couillard et al, U.S. Pat. No. 6,139,004, the apparatus comprising a contour-changing conveyance surface. The apparatus utilizes a rotating transfer element which comprises rotating transfer surfaces. The transfer surface secures a strip of material that is running on a conveyer in the opposite direction to the web of material, and the transfer element then rotates to align the strip with a moving web of material. As it does this, the transfer surface also rotates about an axis which is perpendicular to the axis of the transfer element, such that the strip is positioned so it is placed in a transverse orientation on the moving web of material.
A problem with such an apparatus is that in at least one embodiment, the transfer element is in contact with both the conveyer carrying the strip and the moving web of material. Such an embodiment would require the strip material and web of material to have matched speeds. This then limits the frequency of placement of the strip material onto the web by the length of the strip material. In order to change the frequency of placement of the strip material, the diameter of the transfer element would need to be altered.
Another problem with the above mentioned technologies is that they require the strip of tape material to be handled on both sides during the transfer process; usually because the tape material is presented to the transfer element on a conveyer. This is inconvenient, especially if it is desired that at least one side comprise an adhesive substance.
A further problem is that current technologies require complex manipulation to re-orientate the desired length of tape material during the transfer process. Complex apparatuses tend to suffer increased mechanical wear, in turn increasing maintenance costs. This can result in lower rates of product throughput.
There is a need in the art to provide an apparatus for placing lengths of tape material in a transverse orientation onto a moving web of material, wherein only one side of the length of tape material needs to be handled by the apparatus during the transfer process. There is a further need in the art for an apparatus for placing lengths of tape material in a transverse orientation onto a moving web of material, wherein the frequency of placement of the tape material onto the web is independent of the length of the tape material. There is a further need to provide a cheap, simple, low maintenance apparatus that has a high product through-put capability.
The present invention offers an apparatus and method for placing a desired length of tape material moving in a first direction onto a moving web of material, moving in a second direction, in a transverse orientation, wherein the desired length of tape material is only handled on one side during the transfer process. Furthermore, the placement frequency of the desired length of tape material onto the moving web of material is independent of the length of the desired length of tape material when the tape material and the web of material are moving at matched speeds. The apparatus is also simple, cheap and of low maintenance comprising few complex components.